1630s, "to feel sick, to become affected with nausea" (intrans.), from nauseat- past-participle stem of Latin nauseare "to feel seasick, to vomit," also "to cause disgust," from nausea (see nausea). Related: Nauseated; nauseating; nauseatingly. In its early life it also had transitive senses of "to reject (food, etc.) with a feeling of nausea" (1640s), also figurative, "to loathe, to reject with disgust." Meaning "to create a loathing in, to cause nausea" is from 1650s. Careful writers use nauseated for "sick at the stomach" and reserve nauseous (q.v.) for "sickening to contemplate."